Induction of experimental amyloidosis in neonatally thymectomized mice.

Outbred Swiss albino mice thymectomized at birth show a marked lymphocyte depletion and a striking impairement of the capacity to form antibodies against sheep red blood cells (RBC) and to reject allogeneic skin grafts, as compared to sham-operated controls, but rarely exhibit symptoms of wasting disease. Neonatal ablation of the thymus neither significantly modifies the susceptibility of mice chronically exposed to casein to develop amyloidosis nor does it lessen the gravity of the disease, when compared to sham-operated controls. These results are interpreted as evidence against an autoimmune pathogenesis of the casein-induced experimental amyloidosis. However, some reservations are imposed by recent data which hint at the possibility that thymectomy may sometimes favour, instead of repress, the development of autoimmune diseases in man and rodents.